Vertical tapered spline broaching machine



March 14, 1939. 1: WEST VERTICAL TAPERED SPLINE BROACHING MACHINE Filed July 9, 1936 5' Sheets-Shet 1 dmmzzdjz est.

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VERTICAL TAPERED SI LINE BROACHING MACHINE 5 Sheet Sheet 2 Filed y 1936 March 14,1939. H WEST 2,150,593

VERTICAL TAPERED SPLINE B ROACHING MACHINE I Filed July 9, 1936 5 Sheets-Sheet- 3 .wm, m ww w w wnw Inz/erzr Jam/12K Wesa WW. mnN h I vi .4 A @i H 4. \Mfiw & NT M A E V v w M \v a S M \c i R L NU U A v mm M a m D. H. WEST VERTICAL TAPERED SPLINE BROACHlNG MACHINE March 14, 1939.

Filed July 9, 1936 5 Sheets-Sheet 4 P'Unlll D. H. WEST March 14, 1939.

VERTICAL TAPERED SPLINE BROACHING MACHINE Filed July 9, 1936 5 Sheets-Sheet 5 Max WNUNW t6 ku mw Q W N Patented Mar. 14, 1939 e I 2,150,593

UNITED STATES PATENT OFFICE VERTICAL TAPERED SPLINE BROACHING MACHINE Donald H. West, Bolton, Mass, assignor to The Lapointe Machine Tool Company, Hudson, Mass., a corporation of Maine Application July 9, 1936, Serial No. 89,730

4 Claims. (Cl. 90-33) This invention relates to a. broaching machine tapered spline or keyway while being cut will of the vertical type and particularly to a machine be vertically positioned. adapted for cutting a plurality of splines or key- Any suitable mechanism for indexing the work ways in a tapered hole. It is apparent that a table I? and the work W may be provided. As 5 multiple broach cannot be used for such work shown in the drawings, the table I1 is associated on account of the generally conical disposition with a worm gear l8 (Fig. 3) which is engaged of the splines or keyways. by a worm l9 (Fig. 3 intermittently rotated It is the general object of my invention to proby an index mechanism 20 through a drive shaft vide a machine in which the splines are cut sep- 2 I, bevel gears 22 and worm shaft 23.

arately and successively by a single broaching The table I! and worm gear 18 are mounted l0 cutter and in which the work is indexed between torock about the axis of the Worm shaft 23 successive cuts. when the table is moved to a selected inclined A further object is to provide a machine in position, and the pin-and-slot connection inwhich the work and broach are relatively sepdicated at 25 (Fig. 3) permits limited sliding arated during the idle return stroke of the movement of the platen I5 and work table ll 15 broach, preferably by moving the work away toward or away from the index mechanism 20, from the broach. This latter arrangement peras will be hereinafter described. A separate momits the broach to be held in working position tor M may be provided for the index mechanism. and without removal until the entire series of The Sliding movement of the platen s e ected tapered plines or keyways h s be n t, by a piston rod 21 (Fig. 3) connected to a piston 20 I have shown my inventi mb di d i a hyin a hydraulic cylinder 28 mounted in fixed posidraulically operated machine, and important 111011 011 the p A p S w 9 l ts features of my invention relate to special con- Outward Sliding mevemehtof e p ate toward structions and arrangements by which hydraulic the breach, and Similar Provision y be mode operation is fa ilitated for adjustably limiting sliding movement in the 26 My invention further relates to arrangements Opposite direction or away from the cachand combinations of parts which will be herein- A bracket 30 (Fig- 3) is mounted on the platen after described and more particularly pointed out and rod Carried by the bracket is in the appended c1aims nected through an arm 3|, rock shaft 3 l arm 3U 30 A preferred form of the invention is shown in a link F leYer 32 through which the 30 the drawings in which index mechanism 20 1s controlled.

Fig. 1 is a side elevation of my improved The mfechamsm 20,15 may be of usual breaching machine; commercial type and in itself forms no part of Fig. 2 is a front elevation thereof, my present invention. For the purposes of this F1 3 i i 1 application it is suflicient to state that when the s, 5 par m1 5 de e eva'tlon on an enlarged platen I5 is shifted to the left in Fig. 3 to move the work away from the broach, the lever 32 is Fig. 3 is a detail plan. view looking in the I moved in a clockwise d1rect1on to start the index directlon oi the arrow 3 in Fig. 3, mechanism in operation.

i 5 am} 6 are dlagrammatm fl The index mechanism then operates through 40 successlye steps m the operatmn of my a predetermined cycle to angularly advance the p p I work W from one keyway to the next. Change Fig. '7 1s a partial side elevation of certain parts gears 20a in the index mechanism 20 may be to h de scnbed; a selectively combined to secure the angular ad- I Fig. 8 1s a detail sectional v1ew on the line 8--8 Vance of the work at each feeding movement 45 m which is required for a particular work item.

Referring to s to improved machine The cylinder 28 for shifting the platen I5 is comprises a base or frame Ill having an upper connected by pipes 33 and 34 (Fig. 4 to -g p t H forming a p st or column a d having 35 and 35 in a Work control valve v, which valve a front portion 12 forming a S p for e guide V is also provided with additional ports con- 50 member M (Fig. 3). A platen I5 is slidable in ne ted to a supply pipe 36 and to a discharge or t guide member and pp ts a work table return pipe 31. The supply pipe 36' is connected I! which is commonly mounted to rotate about to a small pump 38 which has its intake pipe 39 an axis on the platen I5 which is selectively in extending into a tank or reservoir R.

clined with respect to the vertical, so that the The discharge pipe 31 is connected to the cas- 55 ing of a second pump 40 through a filter 4|, and the casing is provided with an outlet pipe 42 discharging into the reservoir R. The passing of oil from the pump 38 through the casing of the larger pump 40 is useful in effectively lubricating the latter pump and in absorbing excess heat.

The pressure or delivery pipe 36 of the pump 38 is also connected through a pipe 44, relief valve 45 and pipe 45 to the discharge or return pipe 31 from the valve V. The purpose of this latter connection will be hereinafter described.

The valve rod 50 (Fig. 4) of the reversing valve V is connected by a link 5I to an arm 52 on a rock shaft 53. The rock shaft 53 is provided with an arm 54 having a cam roll 55 mounted thereon, and the shaft 53 also has an arm 51 connected by a link 58 to an arm 59 on an upper rock shaft 60. a

The shaft 60 is provided with an arm 6| and cam roll 62 corresponding to theparts 54 and 55 previously described.

The rolls 55 and 62 are positioned for engagement by lower and upper cam surfaces 63 and 64 on a block 65 fixed on a vertically slidable rod 66. The connections are such that when the lower roll 55 is engaged by the cam surface 63, the valve rod 50 will be shifted to the left and the upper roll 62 will be advanced into the path of the upper cam surface 64. When the rod 66 thereafter moves upward, the arm 6I will be swung outward and the valve rod 5I will be shifted to the right to reverse the hydraulic connections of the work control valve V;

The rod 66 is secured to the lower part of the ram or slide I0 which actuates the pull broach B. The broach is secured at its lower end in a pull socket or holder 'II and is slidable in a broach guide I2 (Figs. 3 and 8), the upper end of which extends through a bushing I3 on a bracket I4 fixed to the post or column I I.

The lower end of the broach guide I2 is seated in a recess or socket fixed in position below the work W and the platen I 5. The broach guide 72 is secured in working position by a clamping screw I5 on the bracket 14. When it is desired to change the work, the screw I5 is loosened and the broach guide I2 is pulled upward through the bushing I3. The work can then be removed and replaced, the broach B being in its extreme downward position.

In order to reduce the over-all height of the machine, the ram or slide I0 is constructed to slide in guideways at each side of the main cylinder 85. It is desirable, however, that the power be applied to the uppermost part of the ram, and for this reason the piston rod 8I which is actuated by the piston 82 in the cylinder is con nected to a cross head 83 (Fig. '7) which is below and entirely separate from the ram I0. Rods 84 extend upward from the cross head 83 to offset portions 85 at the upper end of the ram III and are firmly secured to said portions 85. These rods also extend loosely through lower offset portions 86 but have no operative connection therewith.

It will be understood that the portions 85 and is similarly connected by a pipe 93 to a port 95 in the valve C. The pump 40 previously described is provided with an intake pipe 96 from the reservoir R and with a pressure or supply pipe 91 connecting the pump to an opening 98 in the valve C which communicates with a passage 99 and port I 00. The passage 99 communicates with additional ports IEII, I52 and I03.

A four-part piston valve E35 (Fig. 4) has its piston rod I66 connected through an arm I51, rock shaft I58, arm I59 to a link H5. The link I It is connected to an arm IN on a rock shaft H2 and the shaft H2 is connected by a. link H3 and an arm IM to a handle H5.

The rock shaft I2 is also connected by an arm I 25 and link I2I to a rod I22 vertically slidable in fixed bearings I23 and I24 and provided with upper and lower collars I25 and I26 respectively.

The rod I22 extends loosely through a vertical opening in the block 55 and the collars I25 and I26 are engaged alternately by the upper and lower surfaces of the block 65 as the rod 65 and block 55 are moved vertically with the ram III and broach B and approach their upper or lower limits of travel.

The control valve C is provided with an additional port I30 connected through a pipe I3I and needle valve I32 to the pipe I33 which discharges into the reservoir R. A port I35 in the valve C is connected by a pipe I36 to the pipe I33 previously described.

The pump 40 is preferably of the variable discharge type and may be actuated by a constant speed motor M. The discharge of the pump may be selectively adjusted manually by a control lever I40 (Fig. 1). The pump 40 is provided with the usual gauge I31, connected to show the pressure on the discharge side of the pump.

Having described the details of construction of my improved vertical broaching machine, I will first describe the general operation of the machine and will then describe in detail the operation of the hydraulic mechanism.

The work W having been secured on the rotating work table H, the broachguide I2 is inserted downward through the bushing 13 (Fig. 3) and is secured by the clamping screw I5. The work table at this time has been shifted to the left and is out of contact with the broach.

The ram or slide "I0 is then caused to move upward, after which the work is shifted to the right in Fig. 3. The broach is given an operative downward movement, cutting the first tapered spline or keyway in the internal wall of the opening in the hub of the work.

As the broach approaches its lower limit of travel, the lower cam surface 63 of the block 65 engages the lower roll 55, which in turn reverses the valve V which controls the. platen cylinder 28. This reversal of the valve V causes the piston in the platen cylinder 23 to be moved to shift the work to the left, so that the broach is clear in the axial opening in the hub-of the work. 7 This shifting movement of the work away from the broach also acts through the connections de scribed to start the index mechanism, which then advances the work angularly to the next broaching position while the broach is out of contact there-with. I

As the downward travel of the broach is fully completed, the block 65 engages the collar I26 on the rod I22 and acts through the connections shown in Fig. 4 to shift the control valve C, thus reversing the travel of the piston 82 and caus- 1 5,

ing the slide 10 and broach B to be moved upward to initial position.

The cycle of operations is then again repeated, the broach cutting a new keyway on each downward movement and the index mechanism advancing the work angularly after the completion of each cut and while the broach is out of contact with the work.

This cycle of operation is repeated automatically until the desired number of keyways has been out in the work, and the machine may then be stopped, either manually or automatically, with the broach in down position. The broach guide- 12 is then removed, the work W is replaced, and another series of breaching cuts will then take place.

In order to prevent the control valve 0 from stopping in neutral position when the machine is operating automatically, I providea plunger I50 (Fig. 1) pivoted tothe link H3 and arm H4 at I5I and slidable in a cylinder I52 mounted to swing on a fixed pivot I53. A spring I54 is housed in the cylinder I52 below the plunger I50. I also provide the link IIO with a slot I55 I to receive a pin I55 in the upper end of the arm The pin and slot connection between the link H0 and the arm I09 allows the link H0 and connected parts to be moved a substantial distance in either direction before the pin I55 engages the end of the slot and communicates motion to the piston rod I06. Consequently when the block 55 engagesone of the collars on the vertical rod I22 and moves the arms I20 and III, links H0 and H3, and arm II 4, these parts will be brought to mid-position before the control valve 0' is brought to mid or neutral position.

The hydraulic connections will thus still be effective to continue movement of the block 65 and associated parts until the toggle pin I5I is beyond the center line, after which the spring I54 will exert pressure to complete the movement of the valve. In this way the stalling of the machine on reversal is effectually avoided.

The handle I I5 is used to start the machine in operation and may be used to stop the machine at any desired point in the series of broaching operations or when the work is completed.

The hydraulic mechanism herein described possesses special advantages in the operation of this particular type of broaching machine and the operation and advantages thereof will now be described.

The parts are shown in Fig. 4 with the control valve C in mid or neutral position and with the valve V in position to move the piston rod 27, together with the worktable. and work, to the left to clear the broach. Such movement also renders the index mechanism operative.

The heavy lines in the diagram indicate flow of oil under pressure, the light lines indicate flow of exhaust or discharge oil from the cylinders, and the dotted lines indicate connections in which no flow of oil is taking place.

Referring to Fig. 4, oil under pressure is conducted from the pump 38 through the pipe 36 and port 35 to the pipe 33 which connects with the right-hand end of the platen cylinder 28. The left-hand or exhaust end of the cylinder 28 is connected through the pipe 34 and. port 35 to the exhaust connection 31. Oil flowing through this exhaust connection is filtered at M and is then passed through the casing of the main pump 40 in its return travel to the reservoir R. The oil discharged from the platen cylinder 28 thus performs a cooling function in the pump 40.

Flow of oil from. the pump 38 will continue as described until the platen reaches its limit of movement, after which the pump38 will discharge through the pipe 44, relief valve 45' and by-pass connection 40 into the return line 31 previously described.

As the control valve C is in mid-position, the discharge of the main pump 40 is by-passed through the pipe 9?, port 98, passage. 99, port I03, port I35, pipe I36 and pipe I33 back to the reservoir R. At the same time the ports BI and 05 are closed in the valve 0, so that no flow of oil can take place either toward or away from either end of the main cylinder and consequently the ram or slide I0 is locked in fixed vertical position. This is a valuable safety feature, as it makes downward movement of the ram impossible when the machine is not in operation.

The position of the parts during the working or downward stroke of the ram I0 is indicated in Fig. 5. The pump 38 continues to discharge through the pipe 44, relief valve 45 and by-pass 46 to the return line 31 as previously described. The piston valve in the control valve mechanism C has been shifted to the right, so that oil under pressure in the passage 99 is now conducted through the ports I02 and 9! to the pipe which is connected to the upper end of the main cylinder 80.

The discharge from the lower end of the cylinder is conducted through the ports and I30 to the pipe I3I, which is connected through the needle valve I32 to the pipe I33 which discharges into the reservoir R. The needle valve I32 may be set manually to maintain any desired back pressure under the piston 82 in the main cylinder 80.

The position of the parts during the return stroke is indicated in Fig. 6, the valve in the control mechanism C having been shifted to the left. The pump 38 continues to discharge through the relief valve 45 as previously described. The main pump 40 now delivers oil from the passage 99 through the ports IOI and 95 to the pipe 93 which is connected to the lower end of the cylinder 80.

The upper end of the cylinder 80 is connected through the pipe 90, port 9|, port I35 and pipe I36 to the return pipe I33 which discharges intothe reservoir R.

It will be noted that during the upward movement of the ram or slide 10, the discharge is by-passed around the needle valve I32, so that back pressure is maintained only during the downward stroke. The same by-pass connection through the pipe I 36 is also used during the idle operation of the pump 40 when the machine is in neutral position.

I have thus provided very simple hydraulic mechanism by which the broach may be operated at any desired speed and may be stopped and locked in any desired position and. by which the work may be automatically indexed at the completion of each cut.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:,

1. In a breaching machine, a hydraulic cylin-- der, piston and piston rod, a Work support, a ram, control means effective to cause said piston to move said piston rod downward on a working stroke and upward on a return stroke, a cross head separate from said ram and attached to said piston rod below said ram, and a pair of spaced pull rods positioned substantially in a plane with said piston connected between said cross head and points of attachment on the upper portion of said ram.

2. In a broaching machine, a hydraulic cylinder, piston and piston rod, a work support, a ram, control means effective to cause said piston to move said piston rod downward on a working stroke and upward on a return stroke, a cross head separate from said ram and attached to said piston rod below said ram, and pull rods connected between said cross head and points of attachment on upper spaced portions of said ram, said rods extending freely through openings in lower spaced portions of said ram but being free therefrom.

3. In a vertical broaching machine having a broach, an annular rotatable work support, means to reciprocate said breach along a fixed path within said annular work support and in an axial opening in the work, means to shift the work support to move the axis of the work away from the broach to clear the broach at the end of the cutting stroke and to return said work support to operative position at the end of the return stroke of said breach, and means to angularly index the work support and work, that improvement which consists in providing a direct control connection between said work support and said indexing means through which direct connection said indexing means is rendered operative to advance the work support and work angularly by movement of the work support away from breaching position.

4. In a broaching machine having hydraulic breach-operating mechanism, in combination, a control valve for said mechanism, a valve actuating member, automatic means to move said actuating member to shift said control valve to a reverse operating position at each end of the broach travel, spring toggle means to complete the movement of said actuating member in each direction, and a lost motion connection between said member and valve so constructed and arranged that said spring toggle means is given a lead on said valve when operated in either direction, whereby said valve remains in each operative position until said spring toggle means has been automatically shifted across dead center relative thereto.

' DONALD H. WEST. 

